#! /usr/bin/python

from datetime import date
import getopt
import os
import re
import sys
import xml.dom.minidom

import ovs.json
from ovs.db import error
import ovs.db.schema

argv0 = sys.argv[0]

def textToNroff(s, font=r'\fR'):
    def escape(match):
        c = match.group(0)
        if c.startswith('-'):
            if c != '-' or font == r'\fB':
                return '\\' + c
            else:
                return '-'
        if c == '\\':
            return r'\e'
        elif c == '"':
            return r'\(dq'
        elif c == "'":
            return r'\(cq'
        else:
            raise error.Error("bad escape")

    # Escape - \ " ' as needed by nroff.
    s = re.sub('(-[0-9]|[-"\'\\\\])', escape, s)
    if s.startswith('.'):
        s = '\\' + s
    return s

def escapeNroffLiteral(s):
    return r'\fB%s\fR' % textToNroff(s, r'\fB')

def inlineXmlToNroff(node, font):
    if node.nodeType == node.TEXT_NODE:
        return textToNroff(node.data, font)
    elif node.nodeType == node.ELEMENT_NODE:
        if node.tagName in ['code', 'em', 'option']:
            s = r'\fB'
            for child in node.childNodes:
                s += inlineXmlToNroff(child, r'\fB')
            return s + font
        elif node.tagName == 'ref':
            s = r'\fB'
            if node.hasAttribute('column'):
                s += node.attributes['column'].nodeValue
                if node.hasAttribute('key'):
                    s += ':' + node.attributes['key'].nodeValue
            elif node.hasAttribute('table'):
                s += node.attributes['table'].nodeValue
            elif node.hasAttribute('group'):
                s += node.attributes['group'].nodeValue
            else:
                raise error.Error("'ref' lacks required attributes: %s" % node.attributes.keys())
            return s + font
        elif node.tagName == 'var':
            s = r'\fI'
            for child in node.childNodes:
                s += inlineXmlToNroff(child, r'\fI')
            return s + font
        else:
            raise error.Error("element <%s> unknown or invalid here" % node.tagName)
    else:
        raise error.Error("unknown node %s in inline xml" % node)

def blockXmlToNroff(nodes, para='.PP'):
    s = ''
    for node in nodes:
        if node.nodeType == node.TEXT_NODE:
            s += textToNroff(node.data)
            s = s.lstrip()
        elif node.nodeType == node.ELEMENT_NODE:
            if node.tagName in ['ul', 'ol']:
                if s != "":
                    s += "\n"
                s += ".RS\n"
                i = 0
                for liNode in node.childNodes:
                    if (liNode.nodeType == node.ELEMENT_NODE
                        and liNode.tagName == 'li'):
                        i += 1
                        if node.tagName == 'ul':
                            s += ".IP \\(bu\n"
                        else:
                            s += ".IP %d. .25in\n" % i
                        s += blockXmlToNroff(liNode.childNodes, ".IP")
                    elif (liNode.nodeType != node.TEXT_NODE
                          or not liNode.data.isspace()):
                        raise error.Error("<%s> element may only have <li> children" % node.tagName)
                s += ".RE\n"
            elif node.tagName == 'dl':
                if s != "":
                    s += "\n"
                s += ".RS\n"
                prev = "dd"
                for liNode in node.childNodes:
                    if (liNode.nodeType == node.ELEMENT_NODE
                        and liNode.tagName == 'dt'):
                        if prev == 'dd':
                            s += '.TP\n'
                        else:
                            s += '.TQ\n'
                        prev = 'dt'
                    elif (liNode.nodeType == node.ELEMENT_NODE
                          and liNode.tagName == 'dd'):
                        if prev == 'dd':
                            s += '.IP\n'
                        prev = 'dd'
                    elif (liNode.nodeType != node.TEXT_NODE
                          or not liNode.data.isspace()):
                        raise error.Error("<dl> element may only have <dt> and <dd> children")
                    s += blockXmlToNroff(liNode.childNodes, ".IP")
                s += ".RE\n"
            elif node.tagName == 'p':
                if s != "":
                    if not s.endswith("\n"):
                        s += "\n"
                    s += para + "\n"
                s += blockXmlToNroff(node.childNodes, para)
            elif node.tagName in ('h1', 'h2', 'h3'):
                if s != "":
                    if not s.endswith("\n"):
                        s += "\n"
                nroffTag = {'h1': 'SH', 'h2': 'SS', 'h3': 'ST'}[node.tagName]
                s += ".%s " % nroffTag
                for child_node in node.childNodes:
                    s += inlineXmlToNroff(child_node, r'\fR')
                s += "\n"
            else:
                s += inlineXmlToNroff(node, r'\fR')
        else:
            raise error.Error("unknown node %s in block xml" % node)
    if s != "" and not s.endswith('\n'):
        s += '\n'
    return s

def typeAndConstraintsToNroff(column):
    type = column.type.toEnglish(escapeNroffLiteral)
    constraints = column.type.constraintsToEnglish(escapeNroffLiteral,
                                                   textToNroff)
    if constraints:
        type += ", " + constraints
    if column.unique:
        type += " (must be unique within table)"
    return type

def columnGroupToNroff(table, groupXml):
    introNodes = []
    columnNodes = []
    for node in groupXml.childNodes:
        if (node.nodeType == node.ELEMENT_NODE
            and node.tagName in ('column', 'group')):
            columnNodes += [node]
        else:
            if (columnNodes
                and not (node.nodeType == node.TEXT_NODE
                         and node.data.isspace())):
                raise error.Error("text follows <column> or <group> inside <group>: %s" % node)
            introNodes += [node]

    summary = []
    intro = blockXmlToNroff(introNodes)
    body = ''
    for node in columnNodes:
        if node.tagName == 'column':
            name = node.attributes['name'].nodeValue
            column = table.columns[name]
            if node.hasAttribute('key'):
                key = node.attributes['key'].nodeValue
                if node.hasAttribute('type'):
                    type_string = node.attributes['type'].nodeValue
                    type_json = ovs.json.from_string(str(type_string))
                    if type(type_json) in (str, unicode):
                        raise error.Error("%s %s:%s has invalid 'type': %s" 
                                          % (table.name, name, key, type_json))
                    type_ = ovs.db.types.BaseType.from_json(type_json)
                else:
                    type_ = column.type.value

                nameNroff = "%s : %s" % (name, key)

                if column.type.value:
                    typeNroff = "optional %s" % column.type.value.toEnglish(
                        escapeNroffLiteral)
                    if (column.type.value.type == ovs.db.types.StringType and
                        type_.type == ovs.db.types.BooleanType):
                        # This is a little more explicit and helpful than
                        # "containing a boolean"
                        typeNroff += r", either \fBtrue\fR or \fBfalse\fR"
                    else:
                        if type_.type != column.type.value.type:
                            type_english = type_.toEnglish()
                            if type_english[0] in 'aeiou':
                                typeNroff += ", containing an %s" % type_english
                            else:
                                typeNroff += ", containing a %s" % type_english
                        constraints = (
                            type_.constraintsToEnglish(escapeNroffLiteral,
                                                       textToNroff))
                        if constraints:
                            typeNroff += ", %s" % constraints
                else:
                    typeNroff = "none"
            else:
                nameNroff = name
                typeNroff = typeAndConstraintsToNroff(column)
            body += '.IP "\\fB%s\\fR: %s"\n' % (nameNroff, typeNroff)
            body += blockXmlToNroff(node.childNodes, '.IP') + "\n"
            summary += [('column', nameNroff, typeNroff)]
        elif node.tagName == 'group':
            title = node.attributes["title"].nodeValue
            subSummary, subIntro, subBody = columnGroupToNroff(table, node)
            summary += [('group', title, subSummary)]
            body += '.ST "%s:"\n' % textToNroff(title)
            body += subIntro + subBody
        else:
            raise error.Error("unknown element %s in <table>" % node.tagName)
    return summary, intro, body

def tableSummaryToNroff(summary, level=0):
    s = ""
    for type, name, arg in summary:
        if type == 'column':
            s += ".TQ %.2fin\n\\fB%s\\fR\n%s\n" % (3 - level * .25, name, arg)
        else:
            s += ".TQ .25in\n\\fI%s:\\fR\n.RS .25in\n" % name
            s += tableSummaryToNroff(arg, level + 1)
            s += ".RE\n"
    return s

def tableToNroff(schema, tableXml):
    tableName = tableXml.attributes['name'].nodeValue
    table = schema.tables[tableName]

    s = """.bp
.SH "%s TABLE"
""" % tableName
    summary, intro, body = columnGroupToNroff(table, tableXml)
    s += intro
    s += '.SS "Summary:\n'
    s += tableSummaryToNroff(summary)
    s += '.SS "Details:\n'
    s += body
    return s

def docsToNroff(schemaFile, xmlFile, erFile, title=None, version=None):
    schema = ovs.db.schema.DbSchema.from_json(ovs.json.from_file(schemaFile))
    doc = xml.dom.minidom.parse(xmlFile).documentElement

    schemaDate = os.stat(schemaFile).st_mtime
    xmlDate = os.stat(xmlFile).st_mtime
    d = date.fromtimestamp(max(schemaDate, xmlDate))

    if title == None:
        title = schema.name

    if version == None:
        version = "UNKNOWN"

    # Putting '\" p as the first line tells "man" that the manpage
    # needs to be preprocessed by "pic".
    s = r''''\" p
.TH "%s" 5 "%s" "Open vSwitch" "Open vSwitch Manual"
.\" -*- nroff -*-
.de TQ
.  br
.  ns
.  TP "\\$1"
..
.de ST
.  PP
.  RS -0.15in
.  I "\\$1"
.  RE
..
.SH NAME
%s \- %s database schema
.PP
''' % (title, version, textToNroff(schema.name), schema.name)

    tables = ""
    introNodes = []
    tableNodes = []
    summary = []
    for dbNode in doc.childNodes:
        if (dbNode.nodeType == dbNode.ELEMENT_NODE
            and dbNode.tagName == "table"):
            tableNodes += [dbNode]

            name = dbNode.attributes['name'].nodeValue
            if dbNode.hasAttribute("title"):
                title = dbNode.attributes['title'].nodeValue
            else:
                title = name + " configuration."
            summary += [(name, title)]
        else:
            introNodes += [dbNode]

    s += blockXmlToNroff(introNodes) + "\n"

    s += r"""
.SH "TABLE SUMMARY"
.PP
The following list summarizes the purpose of each of the tables in the
\fB%s\fR database.  Each table is described in more detail on a later
page.
.IP "Table" 1in
Purpose
""" % schema.name
    for name, title in summary:
        s += r"""
.TQ 1in
\fB%s\fR
%s
""" % (name, textToNroff(title))

    if erFile:
        s += """
.\\" check if in troff mode (TTY)
.if t \{
.bp
.SH "TABLE RELATIONSHIPS"
.PP
The following diagram shows the relationship among tables in the
database.  Each node represents a table.  Tables that are part of the
``root set'' are shown with double borders.  Each edge leads from the
table that contains it and points to the table that its value
represents.  Edges are labeled with their column names, followed by a
constraint on the number of allowed values: \\fB?\\fR for zero or one,
\\fB*\\fR for zero or more, \\fB+\\fR for one or more.  Thick lines
represent strong references; thin lines represent weak references.
.RS -1in
"""
        erStream = open(erFile, "r")
        for line in erStream:
            s += line + '\n'
        erStream.close()
        s += ".RE\\}\n"

    for node in tableNodes:
        s += tableToNroff(schema, node) + "\n"
    return s

def usage():
    print """\
%(argv0)s: ovsdb schema documentation generator
Prints documentation for an OVSDB schema as an nroff-formatted manpage.
usage: %(argv0)s [OPTIONS] SCHEMA XML
where SCHEMA is an OVSDB schema in JSON format
  and XML is OVSDB documentation in XML format.

The following options are also available:
  --er-diagram=DIAGRAM.PIC    include E-R diagram from DIAGRAM.PIC
  --title=TITLE               use TITLE as title instead of schema name
  --version=VERSION           use VERSION to display on document footer
  -h, --help                  display this help message\
""" % {'argv0': argv0}
    sys.exit(0)

if __name__ == "__main__":
    try:
        try:
            options, args = getopt.gnu_getopt(sys.argv[1:], 'hV',
                                              ['er-diagram=', 'title=',
                                               'version=', 'help'])
        except getopt.GetoptError, geo:
            sys.stderr.write("%s: %s\n" % (argv0, geo.msg))
            sys.exit(1)

        er_diagram = None
        title = None
        version = None
        for key, value in options:
            if key == '--er-diagram':
                er_diagram = value
            elif key == '--title':
                title = value
            elif key == '--version':
                version = value
            elif key in ['-h', '--help']:
                usage()
            else:
                sys.exit(0)

        if len(args) != 2:
            sys.stderr.write("%s: exactly 2 non-option arguments required "
                             "(use --help for help)\n" % argv0)
            sys.exit(1)

        # XXX we should warn about undocumented tables or columns
        s = docsToNroff(args[0], args[1], er_diagram, title, version)
        for line in s.split("\n"):
            line = line.strip()
            if len(line):
                print line

    except error.Error, e:
        sys.stderr.write("%s: %s\n" % (argv0, e.msg))
        sys.exit(1)

# Local variables:
# mode: python
# End:
